Fuel injecting device



Feb. 17, 1942. A. v. ZANETTI FUEL INJECTING DEVICE Filed Dec. 5, 1938 PatenteJFeb. 17, 1942 NITE STATES PATENT OFFICE,

FUEL INJECTING DEVICE Augustus v. Zanetti, Clifton, N. J. Application December 5, 1938, Serial No. 244,692

1 Claim.

atomization of the fuel oil so as to mix with a maximum'amount of air upon introduction into the compression chamber of the engine. 7 An important object of my invention is to pro- .vide a device of the character described wherein the fuel orifices are so constructed as to simplify the manufacturing of .the nozzle tips by eliminating the tedious and diflicult operations of drilling a large number of relatively small holes in the nozzle tip as has heretofore been the practice and which, in some instances, said holes are of diameters of .007" and with tolerances of .0002".

other objects and advantages will be apparent from the following description, appended claim and annexed drawing.

Referring to the drawing wherein like reference'charac'ters designate like parts throughout the several views: t

Figure 1 is a vertical sectional view, partly in elevation, of a nozzle constructed in accordance with my 'invention.

Figure 2 is a plan view of the nozzle tip.

Figure 3 is a sectional view taken on the line 3-3 of Figure '1.

In practicing my invention, I provide a fuel injector nozzle 5 comprising a nozzle retaining sleeve 6 fitted within a wall I of a cylinder head.

The lower end of the nozzle sleeve is reduced on the periphery thereof to' form a shoulder for engagement with a gasket 8 fitted on a similar shaped shoulder in the opening of the cylinder wall through which the sleeve extends.- The up-'- per end of the sleeve'G has threaded therein the lower threaded end of an injector body 9 and which is fashioned with a longitudinally extending passage 9a connected by means of a pipe III to a pump for feeding fuel oil into the device.

Mounted in the sleeve 6 subjacent the lower end of the body is an injector valve cylinder Illa 'and which is formed with a lengthwise extending fuel passage II, the upper end of which comorifices 22.

of the passage communicates with a fuel oil chamber l2 formed in said valve cylinder above the lower end thereof. The valve cylinder la is fashioned above the chamber |2 with a centrally disposed bore IS in which is slidably mounted a valve stem I4. I The lower end of the valve stem l is shouldered as at a and formed with a reduced shank l5 normally disposed within the chamber l2.

The lower end of the shank I5 is provided with an inverted frustum shaped valve member l6 seated in a similar shaped seat I! formed in the lower end of the valve cylinder la. The lower end of the valve seat I! communicates with the upper open end of a centrally disposed bore l8. The under face of the cylinder Illa has formed thereon a subjacently extending nozzle tip IS, the upper end of which so: a cylindrical shape and' spaced from the adjacent wall of the sleeve. The'lower end of said tip is of a frustum configuration and has formed therein a plurality of inwardly and upwardly extending fuel oil passages 20, the inner ends of which communicate with the lower end of the cul-de-sac l8. The outer end of the passage 20 communicate with a circumferentially extending groove 2| formed in the peripheral face of the lower end of the tip. The lower face of the tip is recess while the peripheral face adjacent the recess is formed with a plurality of spirally arranged discharge The inner ends of the orifices 22 communicate with the groove 2|. The lower end of the sleeve is formed with a bore having inner and outer oppositely disposed inclined walls 23 and 24 respectively and the wall 23 coacts with the peripheral face of the frustum shaped end of said tip to direct sprays of fuel oil from the groove 2| into the cylinder 22.

The outer face of the cylinder la is provided through the orifices I with a lengthwise extending slot lllb through which any leakage of oil from the tip may flow. The body 9 is provided with a passage 9b communicating' with a groove |0c formed in the upper face of the cylinder and which communicates with the slot I llb for receiving said oil; The

upper end of the passage 9b has connected thereto the end of a pipe through which the oil is discharged into a suitable reservoir or the like.

The upper end of the valve stem I4 is positioned an appreciable distance below thelower municates withthe passage 9a. The lower end ing through the lower end of a bore |0d formed in the body. Slidably mounted in said bore is a spring pressed plunger 25, the lower end of which receives therein the upper end of the projection Me. The upper end of the plunger extends through a bushing 26 threaded into the bore a the upper end of the body.

Mounted on said plunger is a spring 27, the upper end of which engages the lower end of said bushing whereby adjustment of said bushing relative to th'e'body serves to vary the tension of the spring 2! to regulate the actuation of the valve stem M; A lock nut 29 is secured about the upper end of said bushing and serves to lock the latter in adjusted position on the upper end of said body.

In operation, oil is introduced into the chamber I2 through the passages 9a and H and due to the pressure thereof serves to actuate the valve stem 54 upwardly against the tension of the spring 21 and thereby unseat the valve member Hi to permit said oil to be discharged into the cul-de-sac l8 and into the groove 2| through the passages 20. When the oil is. thus discharged into the groove 2|, the same is atomized into the cylinder through the medium of the spirally arranged grooves 22.

From the foregoing it will be apparent that I have provided a simple and eflicient' nozzle equipped with a nozzle tip for maximizing the atomization of the fuel oil whereby to efiect a mixture thereof with a maximum amount of air within the cylinder.

It is obvious that the invention is not confined able. It is therefore to be understood that the invention is not limited to the specific construction as illustrated andidescribed, as the same is only illustrative of the principles of operation,

which are capable of extended application in advance forms, and that the invention comprehcnds all construction within the scope of the appended claim.

What I claim is:

In a. nozzle of the character described, a sleeve reduced at its outer end portion to form a circular centrally disposed discharge orifice therein, the said reduced portion being shaped to form an inner frusto-conical section providing a seat having an increasing taper inward from the orifice and an outer frusto-conical wall flaring outwardly from the orifice, a nozzle member mounted within the sleeve having a frusto-conical tip portion at one end seated on the seat portion of the sleeve, the outer end of the tip having a depression therein shaped to form a fiaring circumferential wall co-extensive with the exterior flaring portion of the sleeve, the said nozzle member having an axial feed bore terminating inwardly of the tip and communicating througha plurality of oblique duets with a circumferential groove in the frusto-conical porto the herein described use therefor as it may tion of the tip, the latter groove forming an annular chamber in conjunction with the seat and communicating with a plurality of spiral shaped ducts formed through the medium of grooves in the tip, and discharging through the orifice through the flaring circumferential wall at the outer end of the tip.

' AUGUSTUS V. ZANET'II. 

